Organic light emitting diodes (OLEDs) have been widely used due to advantages such as good self-luminous characteristics, superior contrast, fast response time, and flexible display.
Full color is implemented from the OLEDs in several manners, such as (a) using three organic light emitting materials in red, green, and blue to emit light directly; (b) using white organic light emitting diode (WOLED) and color filter (CF); and (c) using a light color conversion method cooperated with a blue light emitting layer and a light color conversion layer.
In current OLEDs, CF design of OLEDs requires CF design methodology of a liquid crystal display (LCD). The CF is required to realize a full color display of an LCD. A color filter substrate 1 generally includes a black matrix (BM) 12, RGB color resists 13, a protective layer 14, and photo spacers (PS) 15; a specific structure is as shown in FIG. 1.
In current OLEDs structures, the photo spacers 15 are located over the protective layer 14, thus distance between the WOLED and the color filter substrate 1 is easily increased, resulting in risk of color mixing. In addition, the photo spacers 15 are generally made of organic photoresists that present a color in light yellow and have a certain translucence.